JP6915983B2 - Light emitting device and toning device - Google Patents

Description

The present invention relates to a light emitting device and a toning device.

Patent Document 1 describes an LED element and one of light emission from the LED element as an LED (light emitting diode) light source that hardly changes the outer shape, causes less damage in the process of adjusting the chromaticity, and can easily adjust the chromaticity. A sealing material containing a phosphor that absorbs a portion, converts a wavelength and emits light, and is arranged around the LED element, a recess formed by cutting the sealing material, and a sealing material filled in the entire recess. Describes an LED light source having different chromaticity adjusting resins.

In Patent Document 2, bare chips of light emitting diodes that emit red, green, and blue light are connected to the wiring pattern of the resin substrate, and as a set, a first convex coating layer is provided on the substrate. Described is a bare chip mounting surface light emitting body formed uniformly and adjacent to each other at substantially equal intervals, and further formed with a second coating layer on the entire substrate.

Patent Document 3 includes two or more independently driven light emitting element chips and an integral phosphor layer covering the two or more light emitting element chips, and the thickness of the integral phosphor layer is at least 1. A light emitting device formed so as to be different between a portion covering one light emitting element chip and a portion covering another light emitting element chip is described.

Japanese Unexamined Patent Publication No. 2010-232525 Japanese Unexamined Patent Publication No. 2012-09530 Japanese Unexamined Patent Publication No. 2012-069787

A COB (Chip On Board) light emitting device in which a plurality of light emitting elements such as blue LEDs are mounted on one substrate and sealed with a phosphor-containing resin, and the light from the light emitting elements is wavelength-converted by the phosphor and emitted. Then, for example, the chromaticity of the emitted light differs slightly depending on the thickness of the sealing resin, and the chromaticity shift may occur due to the temperature rise inside the device during driving. However, with such a light emitting device, since the chromaticity cannot be adjusted by the product alone, it is difficult to correct the chromaticity variation for each product and the chromaticity shift during driving.

Therefore, an object of the present invention is to provide a light emitting device and a toning device capable of adjusting the chromaticity of emitted light in a plurality of stages.

A substrate, a resin frame fixed on the substrate, and a plurality of sets of light emitting elements mounted in an area on the substrate surrounded by the resin frame, and for each set, the light emitting elements constituting the set are in series with each other. A plurality of sets of connected light emitting elements and a plurality of sets of connection electrodes provided on a substrate and electrically connected to the plurality of sets of light emitting elements, and some sets of the plurality of sets of light emitting elements A plurality of sets of connection electrodes capable of selectively supplying a drive current to the light emitting element and a phosphor excited by light from the plurality of sets of light emitting elements are mixed to fill the area on the substrate surrounded by the resin frame. It has a sealing resin that is filled in such a manner and integrally seals a plurality of sets of light emitting elements, and the thickness of the sealing resin directly above the plurality of sets of light emitting elements is different for each set. Provided are a light emitting device in which the chromaticity of the light emitted from the sealing resin when only one set of each of the light emitting elements of the above is emitted is different from each other.

In the above light emitting device, the color of the center point centered on the center point of the region on the chromaticity diagram corresponding to one of the plurality of whites classified by the relative color temperature according to the ANSI C78.377 standard. It is preferable that the thickness of the sealing resin at the mounting position of a plurality of sets of light emitting elements is determined so that the chromaticity value of the emitted light falls within the range of ± 2% of the degree value.

A plurality of sets of light emitting elements are mounted on the horizontal mounting surface of the substrate, and the height of the resin frame from the mounting surface gradually increases from one end side of the substrate toward the other end side of the substrate facing one end. It is preferable that the sealing resin seals a plurality of sets of light emitting elements so that the thickness gradually decreases from one end side to the other end side.

The substrate has a mounting surface that is inclined with respect to the horizontal plane, and a plurality of sets of light emitting elements are mounted on the inclined mounting surface. As it is located above, the lower the height on the mounting surface with respect to the horizontal plane, the larger the position, the lower end of the sealing resin extends along the inclined mounting surface, and the upper end of the sealing resin is one horizontal plane. preferable.

The substrate is a circuit that has a uniform thickness, has an opening, is fixed to the upper surface of the mounting substrate, and is provided with a plurality of sets of connection electrodes, and a metal mounting substrate whose upper surface is an inclined mounting surface. It is preferable that the plurality of sets of light emitting elements, which are composed of a substrate, are mounted on the upper surface of the mounting substrate exposed in the opening.

The substrate has a plurality of horizontal planes having different heights in the vertical direction due to the step formed on the upper surface, and a plurality of sets of light emitting elements are mounted at different height positions for each set. The upper end of the sealing resin is preferably one horizontal plane.

The board is a metal mounting board having a plurality of horizontal planes and a circuit board having a uniform thickness, having an opening, fixed to the upper surface of the mounting board, and provided with a plurality of sets of connection electrodes. It is preferable that the plurality of sets of light emitting elements are mounted on the upper surface of the mounting substrate exposed in the opening.

It is preferable that the plurality of light emitting elements constituting the same set all have the same emission wavelength band, and a part of the plurality of sets of light emitting elements has an emission wavelength band different from that of the remaining set of light emitting elements.

Further, a substrate, a resin frame fixed on the substrate, and a plurality of sets of light emitting elements mounted in a region on the substrate surrounded by the resin frame, and each set of light emitting elements constituting the set A plurality of sets of light emitting elements connected in series with each other and a plurality of sets of connection electrodes provided on a substrate and electrically connected to the plurality of sets of light emitting elements, and a part of the plurality of sets of light emitting elements. A region on a substrate surrounded by a resin frame in which a plurality of sets of connection electrodes capable of selectively supplying a drive current to a set of light emitting elements and a phosphor excited by light from the plurality of sets of light emitting elements are mixed. A sealing resin that is filled so as to fill up and integrally seals a plurality of sets of light emitting elements, and a pair of light emitting elements that are connected to at least one of a plurality of sets of connection electrodes and correspond to each other among the plurality of sets of light emitting elements. By supplying a drive current to the light emitting element, it has a constant current power supply that emits light of the chromaticity corresponding to the set through the sealing resin, and the thickness of the sealing resin directly above the plurality of sets of light emitting elements is By being different from each other for each set, a toning device is provided in which the chromaticity of the light emitted from the sealing resin when only one set of each of the plurality of sets of light emitting elements is made to emit light is different from each other.

According to the above-mentioned light emitting device and toning device, the chromaticity of the emitted light can be adjusted in a plurality of stages.

It is a schematic block diagram of a color matching device 1. It is a vertical sectional view of the light emitting device 10 along the line II-II of FIG. It is a top view and a vertical sectional view of a substrate 11. It is the top view and the vertical sectional view of the substrate 11 from which the white resist 19 was removed. It is a figure which shows the example of the connection relation of the LED element 12. It is a table which shows the example of the correspondence relation between the chromaticity of the emitted light and the intensity of the blue light contained in the emitted light. It is a figure which shows the example of the spectrum of the emitted light of a light emitting device 10. It is a chromaticity diagram corresponding to FIG. It is a flowchart which shows the example of the manufacturing process of a light emitting device 10. It is the top view and the vertical sectional view for demonstrating the manufacturing process of a light emitting device 10. It is the top view and the vertical sectional view for demonstrating the manufacturing process of a light emitting device 10. It is a table which shows another example of the correspondence relation between the chromaticity of the emitted light and the intensity of the blue light contained in the emitted light. It is a chromaticity diagram corresponding to FIG. It is a top view and a vertical sectional view of another light emitting device 20. It is a top view and a vertical sectional view of still another light emitting device 30. It is a top view and a vertical sectional view of still another light emitting device 40. It is a vertical cross-sectional view of still another light emitting device 10'. It is a vertical cross-sectional view of still another light emitting device 20'. It is a vertical cross-sectional view of still another light emitting device 30'. It is a vertical cross-sectional view of still another light emitting device 40'. It is a figure which shows another example of the connection relation of the LED element 12. It is a figure which shows another example of the connection relation of the LED element 12.

Hereinafter, the light emitting device and the toning device will be described with reference to the drawings. However, it should be understood that the present invention is not limited to the drawings or embodiments described below.

FIG. 1 is a schematic configuration diagram of the toning device 1. Further, FIG. 2 is a vertical cross-sectional view of the light emitting device 10 along the line II-II of FIG. The color matching device 1 has a light emitting device 10 and a constant current power supply 80, and the light emitting device 10 has a substrate 11, an LED element 12, a resin frame 13, and a sealing resin 14. The light emitting device 10 is a COB LED module in which a plurality of unpackaged LED elements (LED dies) 12 are directly mounted on a substrate 11, and is used as an LED light source for various lighting devices.

FIG. 3 is a top view and a vertical cross-sectional view of the substrate 11. The substrate 11 is composed of a mounting substrate 11A and a circuit board 11B overlaid on the mounting substrate 11A, and a white resist 19 is provided on the upper surface of the circuit board 11B except for a part of the region. FIG. 4 is a top view and a vertical sectional view of the substrate 11 from which the white resist 19 has been removed. The cross-sectional view of FIG. 3 shows the cut surface of the substrate 11 along the line III-III in the top view of FIG. 3, and the cross-sectional view of FIG. 4 also follows the line IV-IV in the top view of FIG. The cut surface of the substrate 11 is shown.

The mounting substrate 11A is, for example, a flat metal substrate made of aluminum having excellent heat resistance and heat dissipation, on which a plurality of LED elements 12 are mounted, and has a rectangular shape having a size of about several cm square. Has. The mounting substrate 11A also functions as a heat radiating substrate that dissipates heat generated by the LED element 12 and the particles of the phosphor described later. The material of the mounting substrate 11A may be another metal such as copper as long as it has excellent heat resistance and heat dissipation.

The circuit board 11B is an insulating substrate such as a glass epoxy substrate, and as an example, has a rectangular shape having the same size as the mounting substrate 11A. The end of the circuit board 11B is aligned with the end of the mounting board 11A, and the lower surface is attached to and fixed to the upper surface of the mounting board 11A by, for example, an adhesive sheet. As shown in FIGS. 3 and 4, a circular opening (through hole) 111 is formed in the center of the circuit board 11B.

Further, as shown in FIG. 4, six wiring patterns 171 to 176 for supplying electric power to the LED element 12 are provided on the upper surface of the circuit board 11B. Of these, the wiring patterns 171 to 173 surround the upper half of the opening 111 in FIG. 4 and extend from there toward the upper left corner of the circuit board 11B. The wiring patterns 174 to 176 have a shape that is rotationally symmetric (point symmetric) with the wiring patterns 171 to 173 with respect to the center of the circuit board 11B, surround the lower half of the opening 111 in FIG. It extends toward the lower right corner.

As shown in FIG. 3, on the upper surface of the circuit board 11B, six rectangles in which the white resist 19 is not provided and the wiring patterns 171 to 176 are exposed at the two facing corners of the upper left and the lower right. There is a part. These rectangular portions correspond to the connection electrodes 17a to 17c for connecting the light emitting device 10 to the external power source. The connection electrodes 17a to 17c correspond to a set of wiring patterns 171 and 174, a set of wiring patterns 172 and 175, and a set of wiring patterns 173 and 176, respectively. The light emitting device 10 is provided with three sets (3 pairs, 3 systems) of electrodes according to wiring patterns 171 to 176. Each of the connection electrodes 17a to 17c has an anode electrode on one side and a cathode electrode on the other side, and is connected to the constant current power supply 80. In the following, when the connection electrodes 17a to 17c are not distinguished from each other, they are simply referred to as "connection electrode 17".

The LED element 12 is an example of a light emitting device, and is, for example, a blue semiconductor light emitting device (blue LED) composed of an InGaN-based compound semiconductor and having a peak emission spectrum near 450 nm. For example, the LED element 12 has a pair of element electrodes on the upper surface, and the lower surface of the LED element 12 is fixed to the upper surface of the mounting substrate 11A exposed in the opening 111 by a transparent insulating adhesive or the like. .. In the light emitting device 10, a total of 30 LED elements 12 of 6 sets are mounted on the mounting substrate 11A, with 5 LED elements 12 as one set. The element electrodes of the LED elements 12 of the same set are connected to each other by bonding wires 18, and the bonding wires 18 protruding from the LED elements 12 located at the ends of each set are connected to any of the wiring patterns 171 to 176. There is.

FIG. 5 is a diagram showing an example of the connection relationship of the LED element 12. In each of the six sets of LED elements 12, the five LED elements 12 constituting the set are connected in series with each other. The LED element 12 of the set of reference numerals a1 and a2 shown in FIG. 5 is attached to the connection electrode 17a, the LED element 12 of the set of reference numerals b1 and b2 is attached to the connection electrode 17b, and the LED element 12 of the set of reference numerals c1 and c2 is connected to the connection electrode 17c. Are electrically connected to each other.

By connecting one or more of the connection electrodes 17a to 17c to the constant current power supply 80, the light emitting device 10 can selectively supply the drive current to the set of LED elements 12 corresponding to those connection electrodes. Is. In the light emitting device 10, since a plurality of sets of connection electrodes 17a to 17c are provided, a drive current having a predetermined size is independently supplied to the corresponding set of LED elements 12. As will be described later, since the chromaticity of the emitted light from the LED element 12 of the set of a1 to c2 is different from each other, in the light emitting device 10, one or a plurality of sets of a1 to c2 are used according to the desired chromaticity. LED element 12 is driven.

In the light emitting device 10, since all the LED elements 12 are blue LEDs, the plurality of LED elements 12 constituting the same set all have the same light emitting wavelength band. However, not all the LED elements 12 in the light emitting device 10 do not necessarily have the same light emitting wavelength band. For example, some sets of LED elements 12 may be, for example, a green semiconductor light emitting device (green LED) composed of an InGaN-based compound semiconductor and having a peak emission spectrum near 520 nm, and the remaining sets of LED elements 12 may be used. It may have an emission wavelength band different from that of the LED element 12. This point is the same for any of the other light emitting devices described below.

If the drive current can be supplied independently for each group, the connection relationship of the LED elements 12 may be different from that shown in FIG. For example, one set of LED elements 12 may be connected to each set of connection electrodes 17, or the number of sets of LED elements 12 to be connected may be different for each set of connection electrodes 17. Further, each LED element 12 may be flip-chip mounted on the substrate 11 by using solder bumps without using the bonding wire 18.

The resin frame 13 is, for example, a circular frame made of a white or colorless transparent resin, and is a dam material for preventing the sealing resin 14 from flowing out. The resin frame 13 is fixed to the upper surface of the circuit board 11B so as to surround the edge of the opening 111. Therefore, it can be said that the LED element 12 is mounted in the region on the mounting substrate 11A surrounded by the resin frame 13. The resin frame 13 reflects the light emitted laterally from the LED element 12 toward the upper side of the light emitting device 10 which is opposite to the substrate 11 when viewed from the LED element 12.

The sealing resin 14 is, for example, a colorless and transparent resin such as an epoxy resin or a silicon resin in which a yellow phosphor 15 and a red phosphor 16 excited by light from a plurality of LED elements 12 are dispersed and mixed. The sealing resin 14 is filled so as to fill the area on the mounting substrate 11A surrounded by the resin frame 13, and is molded into a hemisphere, for example, and all the LED elements 12 on the substrate 11 are different for each set. It is integrally coated (sealed) with the thickness.

In the light emitting device 10, as shown in FIG. 2, the thickness of the sealing resin 14 increases as the outer peripheral portion closer to the resin frame 13 approaches the center of the substrate 11. Therefore, regarding the pair of a1 and c2 on the outer peripheral portion, the thickness of the sealing resin 14 above the LED element 12 is the same, and the a2 closer to the center of the substrate 11 than the pair of a1 and c2. The thickness of the sealing resin 14 above the LED element 12 is larger in the set of c1 and further in the set of b1 and b2. As a result, in the light emitting device 10, the thickness of the resin layer containing the yellow phosphor 15 and the red phosphor 16 immediately above the LED element 12 is different for each set of the LED elements 12, so that the plurality of sets of the LED elements 12 The chromaticity of the light emitted from the sealing resin 14 when only one set of each is emitted is different from each other. The thickness of the sealing resin 14 may be the same for some sets such as the sets a1 and c2.

The yellow phosphor 15 is a particulate phosphor material that absorbs blue light from the LED element 12 as excitation light and emits yellowish fluorescence. For example, as the yellow phosphor 15, a YAG (yttrium aluminum garnet) -based, delbium-based, strontium-based, phosphate-based, silicate-based, or aluminate-based phosphor is used.

The red phosphor 16 is a particulate phosphor material that absorbs blue light from the LED element 12 as excitation light and emits red light. For example, as the red phosphor 16, _{a CaAlSiN 3} (calcium / aluminum / silicon ^{trinitride) phosphor in which Eu 2+} (Europium) is solid-dissolved is used.

As described above, in the light emitting device 10, the LED element 12 which is a blue LED is covered with the sealing resin 14 in which the yellow phosphor 15 and the red phosphor 16 are mixed. As a result, in the light emitting device 10, when the LED element 12 emits light, the blue light from the LED element 12 and the yellow light and the red light obtained by exciting the yellow phosphor 15 and the red phosphor 16 are obtained, respectively. Are mixed to give white light. The phosphor to be mixed in the sealing resin does not have to be two or more types. For example, two types of blue LED and green LED are used as the LED element 12, and one type of red phosphor is used as the phosphor. You may.

The constant current power supply 80 is connected to at least one of a plurality of sets of connection electrodes 17a to 17c, and supplies a drive current to the corresponding set of LED elements 12 among the plurality of sets of LED elements 12. As a result, the toning device 1 emits light having a chromaticity corresponding to the LED element 12 of the set through the sealing resin 14.

FIG. 6 is a table showing an example of the correspondence between the chromaticity of the emitted light and the intensity of the blue light contained in the emitted light. The percentages of the yellow phosphor and the red phosphor are the weight ratios of the yellow phosphor 15 and the red phosphor 16 to the entire phosphor contained in the sealing resin 14, respectively. The percentage of blue intensity is the intensity ratio of blue light having a wavelength of 450 nm to the entire emitted light of the light emitting device 10. The chromaticity value is the value of the x, y coordinates defined by the CIE (International Commission on Illumination). In the table of FIG. 6, for the cases (1) to (6) in which the compounding ratios of the yellow phosphor 15 and the red phosphor 16 are different, for example, a plurality of light emitting devices 10 having different thicknesses of the sealing resin 14 are prepared. , The magnitude of the drive current of the LED element 12 is fixed, and the intensity ratio (blue intensity) of the blue light to the entire emitted light of each light emitting device 10 is measured and the chromaticity of the emitted light is measured.

The magnitude of the blue intensity varies depending on the thickness of the sealing resin 14 covering the light emitting LED element 12 and the magnitude of the driving current of the LED element 12. For example, if the thickness of the sealing resin 14 is constant, the blue intensity increases as the drive current of the LED element 12 increases, and conversely, the blue intensity decreases as the drive current of the LED element 12 decreases. Further, if the magnitude of the drive current is constant, the thinner the sealing resin 14, the less likely it is that the excitation light by the yellow phosphor 15 and the red phosphor 16 is generated, so that the blue intensity increases, and conversely, the blue intensity increases. The thicker the sealing resin 14, the lower the blue intensity. Therefore, changing the set of the LED elements 12 that emit light in the light emitting device 10 corresponds to changing the blue intensity.

FIG. 7 is a diagram showing an example of the spectrum of the emitted light of the light emitting device 10. The horizontal axis of the graph shows the wavelength λ (nm), and the vertical axis shows the relative intensity L. In the light emitting device 10, the wavelength is 450 nm corresponding to the blue light (B), the yellow light (Y), and the red light (R) generated by the LED element 12, the yellow phosphor 15, and the red phosphor 16, which are blue LEDs. Relative intensity peaks appear near 560 nm and 670 nm. Therefore, in the light emitting device 10, the relative intensity of blue light having a wavelength of 450 nm is used as the blue intensity.

FIG. 8 is a chromaticity diagram corresponding to FIG. The horizontal axis of the graph shows the x-coordinate of the chromaticity, and the vertical axis shows the y-coordinate of the chromaticity. The six straight lines shown in (1) to (6) are loci of chromaticity when the blue intensity is changed in the case of each compounding ratio shown in FIG. 6, and are circles or squares on each straight line. The points indicated by the symbols correspond to the chromaticity values shown in FIG. The eight squares in the graph indicate the white classification (2700K to 6500K) by relative color temperature (CCT) defined by the ANSI (American National Standards Institute) C78.377 standard.

When the blue intensity is changed by changing the set of the LED elements 12 to emit light, the chromaticity of the emitted light differs depending on the compounding ratio of the yellow phosphor 15 and the red phosphor 16 on the chromaticity diagram of FIG. It changes by drawing a linear trajectory. At this time, the chromaticity value moves to the upper right of the graph as the blue intensity increases, and moves to the lower left of the graph as the blue intensity decreases. In particular, if the compounding ratio of the phosphor is set to any of (1) to (6) in FIG. 6 and the blue intensity is changed within the range shown in FIG. 6, the locus of chromaticity is determined by ANSI 2011. It passes through the center coordinates of each defined relative color temperature (CCT) and extends from approximately the lower left to the upper right of the quadrangular region corresponding to one color temperature. Therefore, by adjusting the blue intensity, the light emitting device 10 is emitted along each straight line shown in FIG. 8 within the range of the quadrangular region of any one of (1) to (6) corresponding to the compounding ratio of the phosphor. It becomes possible to adjust the chromaticity of the emitted light.

In particular, the difference between the x-coordinate and y-coordinate of each point on the six straight lines shown in FIGS. 8 (1) to (6) and the x-coordinate and y-coordinate of the center point of each relative color temperature (CCT) is It is within ± 2% of the x-coordinate and y-coordinate of the center point. Therefore, using a blue LED as the LED element 12, the compounding ratio of the phosphor is set to any of (1) to (6) in FIG. 6, and the blue intensity is within the range shown in FIG. If the thickness of the sealing resin 14 at the mounting position of each set of LED elements 12 is determined in this way, the chromaticity of the emitted light can be adjusted within a range of ± 2% from the center point of each relative color temperature (CCT). It becomes possible to do.

The slope of the straight line, which is the locus of chromaticity, is determined by the emission wavelength of the LED element 12. Since the light emitting device 10 uses only the blue LED as the LED element 12, the range in which the chromaticity can be adjusted is limited to one straight line in the chromaticity diagram. However, for example, if some sets of LED elements 12 connected in series are blue LEDs and the remaining set of LED elements 12 are green LEDs, the green intensity (ratio of the intensity of green light to the entire emitted light) changes. By doing so, the chromaticity of the emitted light changes along a straight line having a slope different from that shown in FIG. Therefore, when two types of LED elements 12 are used, a blue LED and a green LED, the chromaticity is adjusted within the two-dimensional region on the chromaticity diagram by changing both the blue intensity and the green intensity. Becomes possible.

FIG. 9 is a flowchart showing an example of a manufacturing process of the light emitting device 10. 10 and 11 are a top view and a vertical sectional view for explaining a manufacturing process of the light emitting device 10. The cross-sectional view of FIG. 10 shows the cut surface of the substrate 11 along the XX line in the top view of FIG. 10, and the cross-sectional view of FIG. 11 also follows the XI-XI line in the top view of FIG. The cut surface of the substrate 11 is shown.

In order to manufacture the light emitting device 10, first, a plurality of COB light emitting devices in which blue LEDs are sealed with different resin thicknesses by sealing resins having the same compounding ratio of the yellow phosphor and the red phosphor are prepared. Will be done. By driving these light emitting devices with a constant current power source 80 and measuring the relative intensity of blue light having a wavelength of 450 nm as the blue intensity, the correspondence between the resin thickness and the blue intensity is measured in advance (S1). Subsequently, the resin thickness corresponding to the blue intensity that gives the desired chromaticity is determined with reference to the correspondence relationship obtained in S1 and the correspondence relationship shown in FIGS. 6 and 8 (S2). That is, for each of the plurality of sets of LED elements 12, the x-coordinate of the chromaticity value of the emitted light is within ± 2% of the chromaticity value of the center point of each relative color temperature (CCT). And the thickness of the sealing resin 14 is determined so that the y-coordinate fits.

After that, as shown in FIG. 10, a plurality of LED elements 12 are mounted in the circular region of the mounting substrate 11A exposed in the opening 111, and the LED elements are individually supplied for each group to which the drive current is independently supplied. 12 is electrically connected by the bonding wire 18 (S3). In the illustrated example, 30 LED elements 12 are mounted, 5 of them are connected in series, and 6 sets of rows of LED elements 12 are a set of wiring patterns 171 and 174, a set of wiring patterns 172, and 175. And are connected between the sets of wiring patterns 173 and 176.

Next, as shown in FIG. 11, the annular resin frame 13 is fixed to the upper surface of the circuit board 11B so as to surround the edge of the opening 111 (S4). Then, the sealing resin 14 in which the yellow phosphor 15 and the red phosphor 16 are mixed in a predetermined blending ratio is filled so as to fill the region on the mounting substrate 11A surrounded by the resin frame 13, and a plurality of sets are formed. Each pair of LED elements 12 is sealed with the thickness determined in S2 (S5). Through the above steps, the light emitting device 10 shown in FIGS. 1 and 2 is obtained.

FIG. 12 is a table showing another example of the correspondence between the chromaticity of the emitted light and the intensity of the blue light contained in the emitted light. The phosphor mixed in the sealing resin 14 is not limited to the yellow phosphor and the red phosphor, and other combinations may be used. In FIG. 12, the yellow phosphor was replaced with a green phosphor, and the blending ratio of the green phosphor and the red phosphor was changed as shown in (1) to (6) to be prepared in the same manner as in the table of FIG. An example of the correspondence between the chromaticity of the emitted light and the intensity of the blue light contained in the emitted light is shown. The green phosphor is a particulate phosphor material such as _{(BaSr) 2} SiO ₄ : Eu ²⁺ , which absorbs blue light from the LED element 12 as excitation light and emits green light. The percentages of the green phosphor and the red phosphor are the weight ratios of the green phosphor and the red phosphor to the entire phosphor contained in the sealing resin 14, respectively. The definitions of the blue intensity and chromaticity values are the same as in FIG.

FIG. 13 is a chromaticity diagram corresponding to FIG. The horizontal axis of the graph shows the x-coordinate of the chromaticity, and the vertical axis shows the y-coordinate of the chromaticity. The six straight lines shown in (1) to (6) are loci of chromaticity when the blue intensity is changed in the case of each compounding ratio shown in FIG. 12, and are circles or squares on each straight line. The points indicated by the symbols correspond to the chromaticity values shown in FIG. The 12 squares in the graph indicate the white classification (2700K to 6500K) by relative color temperature (CCT) defined by the ANSI (American National Standards Institute) C78.377 standard.

Even when a green phosphor is used instead of the yellow phosphor, as in the case of FIG. 8, when the blue intensity is changed by changing the set of the LED elements 12 to emit light, the chromaticity of the emitted light is shown in FIG. On the chromaticity diagram of No. 13, different linear loci are drawn and changed according to the blending ratio of the green phosphor and the red phosphor. In the cases where the compounding ratio of the phosphors is (1) to (4) in FIG. 12, by changing the blue intensity within the range shown in FIG. 12, the locus of chromaticity is set to each relative defined by ANSI 2011. It passes through the central coordinates of the color temperature (CCT) and extends from approximately the lower left to the upper right of the quadrangular region corresponding to one color temperature. However, when a green fluorescent substance is used, when the compounding ratios of the fluorescent substances are (5) and (6) in FIG. 12, the locus of chromaticity is almost the same in the quadrangular regions of 3000K and 2700K, respectively. It extends only in a limited area from the center to the lower left. Therefore, in the light emitting device using the green phosphor and the red phosphor, the light emitting device is along each straight line shown in FIG. 13 within the range of the quadrangular region of any one of (1) to (6) corresponding to the compounding ratio of the phosphor. It becomes possible to adjust the chromaticity of the emitted light.

FIG. 14 is a top view and a vertical sectional view of another light emitting device 20. The cross-sectional view of FIG. 14 shows the cut surface of the light emitting device 20 along the XIV-XIV line in the top view of FIG. The light emitting device 20 includes a substrate 21, an LED element 12, a resin frame 23, and a sealing resin 24, and a yellow phosphor 15 and a red phosphor 16 are mixed in the sealing resin 24. The configuration of the light emitting device 20 is the same as that of the light emitting device 10 except for the shapes of the substrate 21 and the sealing resin 24.

The board 21 is composed of a mounting board 21A and a circuit board 21B. The mounting substrate 21A is a rectangular metal substrate made of aluminum or the like. The circuit board 21B is a rectangular insulating board having a uniform thickness, has a circular opening 211, and is fixed to the upper surface of the mounting board 21A. The circuit board 21B is the same as the circuit board 11B of the light emitting device 10, but unlike the mounting board 11A, the mounting board 21A has a step formed on the upper surface of the exposed portion in the opening 211. It has multiple horizontal planes with different vertical heights. FIG. 14 shows an example in which horizontal planes 221 to 223 having three steps and different heights are formed in three steps.

The LED element 12 of the light emitting device 20 is mounted at different heights on the upper surface of the mounting substrate 21A exposed in the opening 211. For example, the light emitting device 20 also has six sets of a total of 30 LED elements 12 with five LED elements 12 as one set, and each set of LED elements 12 connected in series has the same height on the mounting substrate 21A. It is placed on the horizontal plane. More precisely, two sets of LED elements 12 represented by reference numerals a1 and c2 are arranged on the horizontal plane 221 on the right side and the left side of the cross-sectional view of FIG. 14, respectively. Further, two sets of LED elements 12 represented by reference numerals a2 and c1 are arranged on the two horizontal planes 222 on the central side of the drawing below the horizontal plane 221 and one step lower than the horizontal plane 221. Further, two sets of LED elements 12 represented by reference numerals b1 and b2 are arranged on the lowest horizontal plane 223 in the center of the drawing.

In the light emitting device 10, as shown in FIG. 2, the sealing resin 14 is projected upward from the outer peripheral portion close to the resin frame 13 toward the center, so that the thickness of the sealing resin 14 is increased for each set of the LED elements 12. Is changing. On the other hand, in the light emitting device 20, as shown in FIG. 14, the substrate 21 has a step that becomes lower as it approaches the center from the outer peripheral portion, and the upper surface of the sealing resin 24 is one horizontal plane. In this way, the thickness of the substrate 21 may be changed in a stepped manner so that the sets a1 to c2 of the LED elements 12 are mounted at different heights and connected so that they can be driven independently. Then, by sealing the LED element 12 so that the upper surface of the sealing resin 24 is horizontal, even if the thickness of the sealing resin 14 directly above the LED element 12 is changed for each set of the LED elements 12. good.

FIG. 15 is a top view and a vertical sectional view of yet another light emitting device 30. The cross-sectional view of FIG. 15 shows the cut surface of the light emitting device 30 along the XV-XV line in the top view of FIG. The light emitting device 30 includes a substrate 31, an LED element 12, a resin frame 33, and a sealing resin 34, and a yellow phosphor 15 and a red phosphor 16 are mixed in the sealing resin 34. The configuration of the light emitting device 30 is the same as that of the light emitting device 10 except for the shapes of the substrate 31, the resin frame 33, and the sealing resin 34.

As shown in FIG. 15, in the light emitting device 30, the resin frame 33 is a rectangular frame. The board 31 is composed of a mounting board 31A and a circuit board 31B, and these configurations are the mounting boards of the light emitting device 10 except that the opening 311 of the circuit board 31B is rectangular in accordance with the resin frame 33. It is the same as 11A and the circuit board 11B. Further, the sealing resin 34 is filled so as to fill the region on the mounting substrate 31A surrounded by the resin frame 33, and has a rectangular shape when viewed from above.

In the light emitting device 30, the five sets of LED elements 12 represented by reference numerals a1 to c2 are mounted on the horizontal mounting surface of the mounting substrate 31A, and the height of the resin frame 33 from the mounting surface is on the right side of the drawing. The left side of the figure is higher than that. That is, the height of the resin frame 33 from the mounting surface gradually decreases from one end side (left side in the figure) of the substrate 31 toward the other end side (right side in the figure) of the substrate 31 facing the one end. It has become. Further, the thickness of the sealing resin 34 on the left side of the drawing is the largest, and the thickness decreases toward the right side of the drawing, so that the upper surface of the sealing resin 34 is inclined. That is, the sealing resin 34 seals a plurality of sets of LED elements 12 so that the thickness gradually decreases from one end side of the substrate 31 to the other end side of the substrate 31 facing the one end. In this way, the thickness of the sealing resin directly above the LED element 12 may be changed between the sets of the LED elements 12 that can be driven independently.

FIG. 16 is a top view and a vertical sectional view of yet another light emitting device 40. The cross-sectional view of FIG. 16 shows the cut surface of the light emitting device 40 along the XVI-XVI line in the top view of FIG. The light emitting device 40 includes a substrate 41, an LED element 12, a resin frame 43, and a sealing resin 44, and a yellow phosphor 15 and a red phosphor 16 are mixed in the sealing resin 44. The configuration of the light emitting device 40 is the same as that of the light emitting device 10 except for the shapes of the substrate 41, the resin frame 43, and the sealing resin 44.

The board 41 is composed of a mounting board 41A and a circuit board 41B. The mounting substrate 41A is a rectangular metal substrate made of aluminum or the like. The circuit board 41B is a rectangular insulating board having a uniform thickness, has a circular opening 411, and is fixed to the upper surface of the mounting board 41A. The circuit board 41B is the same as the circuit board 11B of the light emitting device 10, but as shown in FIG. 16, the upper surface of the mounting board 41A, which is the mounting surface of the LED element 12, is different from the mounting board 11A and is on the left side of the drawing. It is tilted with respect to the horizontal plane because it is lower on the right side than on the right side. The LED element 12 of the light emitting device 40 is mounted on the upper surface (inclined surface) of the mounting substrate 41A exposed in the opening 411.

The resin frame 43 is a circular frame like the resin frame 13, but the height of the resin frame 43 from the mounting surface is such that the upper end of the resin frame 43 is located on the same horizontal plane over the entire circumference. , The lower the height on the mounting surface with respect to the horizontal plane, the larger the height. The sealing resin 44 is molded so that the lower end extends along the inclined mounting surface of the substrate 41 and the upper end becomes one horizontal plane. In the light emitting device 40, by sealing the plurality of LED elements 12 in this way, the thickness of the sealing resin 44 increases from the left side of the figure to the right side of the figure. In this way, the thickness of the sealing resin 44 directly above the LED element 12 may be changed between the sets of the LED elements 12 that can be driven independently.

17 to 20 are vertical cross-sectional views of still another light emitting device 10'to 40', respectively. The light emitting devices 10'to 40'have the same configurations as those of the above light emitting devices 10 to 40, except for the configuration of the substrate. The substrates 11'to 41'of the light emitting devices 10'to 40'are not a mounting substrate and a circuit board bonded to each other, but are all one ceramic substrate. The boards 11'to 41'are flat boards having the same wiring patterns 171 to 176 and connection electrodes 17 as described above formed on the upper surface and on which the LED element 12 is mounted, and also serve as a mounting board and a circuit board. ing. As described above, a ceramic substrate having no opening may be used as the substrate of the light emitting device.

Further, in the light emitting devices 10'and 20', the plurality of LED elements 12 are divided into three sets shown by reference numerals a to c in FIGS. 17 and 18, and are separately connected to the three sets of connection electrodes 17. Pairs can be driven independently of each other. In the light emitting devices 30'and 40', the plurality of LED elements 12 are divided into two sets indicated by reference numerals a and b in FIGS. 19 and 20, and are separately connected to two sets of connection electrodes 17. Can be driven independently of each other. As described above, the number of sets of the LED elements 12 may be any number as long as it is two or more sets, and the total number of mounted LED elements 12 may be any number. Further, the number of sets of the connection electrodes 17 may be any number as long as it is two or more sets.

As described above, in the light emitting device 10 (or the light emitting device 20 to 40, 10'to 40'), the thickness of the sealing resin 14 (sealing resin 24 to 44) is set for each set of the LED elements 12 that are independently driven. The set of the LED elements 12 that emit light is switched according to the desired chromaticity. As a result, the toning device 1 can realize a toning function that changes the chromaticity of the light emitting device (LED package) within the same color temperature range defined by ANSI 2011. Further, by having such a color matching function, the light emitting devices 10 to 40, 10'to 40'can also correct the chromaticity shift caused by the temperature change. Therefore, in the light emitting devices 10 to 40, 10'to 40', the design considering the chromaticity shift due to the temperature change becomes unnecessary, and the manufacturing process is further simplified.

21 and 22 are diagrams showing another example of the connection relationship of the LED element 12. In these figures, an example is shown in which three sets of LED elements 12 of reference numerals a to c are connected in parallel, with three or four LED elements 12 connected in series as one set. Reference numerals a and c indicate a set of LED elements 12 mounted in a region where the sealing resin thickness is relatively thin, and reference numerals b mount the LED element 12 in a region where the sealing resin thickness is thicker than the regions designated by reference numerals a and c. Each set of LED elements 12 is shown. The plurality of LED elements 12 in the light emitting device 10 described above may be connected to the constant current power supply 80 as shown in FIG. 21 or FIG.

In FIG. 21, each pair of reference numerals a and c is composed of four LED elements 12. On the other hand, in the set of reference numerals b, the number of LED elements 12 is three, which is one less, and one resistor is connected in series with the LED element 12 instead. In the example of FIG. 21, one or a plurality of sets of LED elements 12 of reference numerals a to c are driven according to the magnitude of the current If from the constant current power supply 80 (variable constant current circuit).

In FIG. 22, the set of reference numerals a is composed of four LED elements 12. The set of reference numeral b is composed of three LED elements 12, and a depletion type FET and a resistor are connected in series to the LED element 12. The set of reference numerals c is composed of three LED elements 12, and resistors are connected in series to the LED elements 12. Also in the example of FIG. 22, one or a plurality of sets of LED elements 12 of reference numerals a to c are driven according to the magnitude of the current If from the constant current power supply 80 (variable constant current circuit).

Further, also in the above-mentioned light emitting devices 20 to 40, 10'to 40', the set of the LED elements 12 mounted in the region where the thickness of the sealing resin is relatively thin and the thickness of the sealing resin are relative to each other. A set of LED elements 12 mounted in a thick region may be connected as shown in FIG. 21 or FIG.

1 Color matching device 10, 10', 20, 20', 30, 30', 40, 40'Light emitting device 11, 11', 21, 21', 31, 31', 41, 41' Substrate 11A, 21A, 31A , 41A Mounting board 11B, 21B, 31B, 41B Circuit board 12 LED element 13, 23, 33, 43 Resin frame 14, 24, 34, 44 Encapsulating resin 15 Yellow phosphor 16 Red phosphor 17, 17a, 17b, 17c Connection electrode 80 constant current power supply

Claims (8)

With the board
The resin frame fixed on the substrate and
A plurality of sets of light emitting elements mounted in a region on the substrate surrounded by the resin frame, and for each set, a plurality of sets of light emitting elements in which the light emitting elements constituting the set are connected in series with each other.
A plurality of sets of connection electrodes provided on the substrate and electrically connected to the plurality of sets of light emitting elements, and selectively driven by some sets of the light emitting elements among the plurality of sets of light emitting elements. With multiple sets of connection electrodes capable of supplying current,
Excited by light from the plurality of sets of light emitting elements , phosphors of a plurality of colors are mixed, and the plurality of sets of light emitting elements are filled so as to fill the sealing region on the substrate surrounded by the resin frame. With a sealing resin that integrally seals the
Since the thickness of the sealing resin directly above the plurality of sets of light emitting elements is different for each set, the light emitted from the sealing resin when only one set of each of the plurality of sets of light emitting elements is made to emit light. The chromaticity of each is different from each other
The depth of the central portion of the sealing region from the upper surface of the sealing resin is deeper than the depth of at least a part of the outer edge of the sealing region from the upper surface of the sealing resin.
The thickness of the sealing resin at the mounting position of the plurality of sets of light emitting elements is on the chromaticity diagram corresponding to one of the plurality of whites classified by the correlated color temperature according to the standard of ANSI C78.377. The plurality of colors with respect to the entire phosphor contained in the sealing resin so that the chromaticity value of the emitted light falls within the range of ± 2% of the chromaticity value of the center point centered on the center point of the region. It is determined according to the weight ratio of the phosphor,
A light emitting device characterized in that. The plurality of sets of light emitting elements are mounted on the horizontal mounting surface of the substrate.
The height of the resin frame from the mounting surface gradually decreases from one end side of the substrate toward the other end side of the substrate facing the one end.
The light emitting device according to claim 1 , wherein the sealing resin seals the plurality of sets of light emitting elements so that the thickness gradually decreases from the one end side to the other end side. The substrate has a mounting surface that is inclined with respect to a horizontal plane.
The plurality of sets of light emitting elements are mounted on the inclined mounting surface, and the plurality of sets of light emitting elements are mounted on the inclined mounting surface.
The height of the resin frame from the mounting surface increases as the height on the mounting surface with respect to the horizontal plane is lower so that the upper end of the resin frame is located on the same horizontal plane over the entire circumference.
The light emitting device according to claim 1 , wherein the upper end of the sealing resin is one horizontal plane. The substrate has a thickness uniform with that of a metal mounting substrate whose upper surface is an inclined mounting surface, has an opening, is fixed to the upper surface of the mounting substrate, and has a plurality of sets of connection electrodes. It is composed of the provided circuit board and
The light emitting device according to claim 3 , wherein the plurality of sets of light emitting elements are mounted on the upper surface of the mounting substrate exposed in the opening. The substrate has a plurality of horizontal planes having different heights in the vertical direction due to the step formed on the upper surface.
The plurality of sets of light emitting elements are mounted at different height positions for each set.
The light emitting device according to claim 1 , wherein the upper end of the sealing resin is one horizontal plane. The substrate has the same thickness as the metal mounting substrate having the plurality of horizontal planes, has an opening, is fixed to the upper surface of the mounting substrate, and is provided with the plurality of sets of connection electrodes. Consists of a circuit board
The light emitting device according to claim 5 , wherein the plurality of sets of light emitting elements are mounted on the upper surface of the mounting substrate exposed in the opening. A plurality of light emitting elements constituting the same set all have the same light emitting wavelength band and have the same light emitting wavelength band.
The light emitting device according to any one of claims 1 to 6 , wherein a part of the plurality of sets of light emitting elements has a light emitting wavelength band different from that of the remaining set of light emitting elements. With the board
The resin frame fixed on the substrate and
A plurality of sets of light emitting elements mounted in a region on the substrate surrounded by the resin frame, and for each set, a plurality of sets of light emitting elements in which the light emitting elements constituting the set are connected in series with each other.
A plurality of sets of connection electrodes provided on the substrate and electrically connected to the plurality of sets of light emitting elements, and selectively driven by some sets of the light emitting elements among the plurality of sets of light emitting elements. With multiple sets of connection electrodes capable of supplying current,
Excited by light from the plurality of sets of light emitting elements , phosphors of a plurality of colors are mixed, and the plurality of sets of light emitting elements are filled so as to fill the sealing region on the substrate surrounded by the resin frame. With a sealing resin that integrally seals
By being connected to at least one of the plurality of sets of connection electrodes and supplying a drive current to the corresponding set of light emitting elements among the plurality of sets of light emitting elements, the color corresponding to the set is passed through the sealing resin. It has a constant current power supply that emits light of degree,
Since the thickness of the sealing resin directly above the plurality of sets of light emitting elements is different for each set, the light emitted from the sealing resin when only one set of each of the plurality of sets of light emitting elements is made to emit light. The chromaticity of each is different from each other
The depth of the central portion of the sealing region from the upper surface of the sealing resin is deeper than the depth of at least a part of the outer edge of the sealing region from the upper surface of the sealing resin.
The thickness of the sealing resin at the mounting position of the plurality of sets of light emitting elements is on the chromaticity diagram corresponding to one of the plurality of whites classified by the correlated color temperature according to the standard of ANSI C78.377. The plurality of colors with respect to the entire phosphor contained in the sealing resin so that the chromaticity value of the emitted light falls within the range of ± 2% of the chromaticity value of the center point centered on the center point of the region. It is determined according to the weight ratio of the phosphor,
A toning device characterized by that.

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